Try for a party of 8 when you need 7 - it's pretty well known here that the Disney ADR system does not like odd numbers, and there's no penalty for showing up with 7 when you booked 8. Trying to add person #7 to a table for 6 when you show up for the ADR can be difficult, especially if the restaurant doesn't have tables that seat more than 6.
For parties larger than 8, I agree with above, try splitting into two parties, for example 6+4, but put the first ADR into the name of one of the other members of the party, then put the second one in your name (if you put the first one into your name, it won't let you book the second one). Then have everyone show up early, check in with the CM in person, not via
MDE, and politely ask to be seated as close together as possible.
You might also try booking for a party of 10 and watch for a pop-up message asking you to call a special number. That happened back in 2020 when I was booking for 9, and the CM who answered that number was extremely helpful -- but even she had to split our party up for some restaurants! We were able to sit together everywhere, though, except Sci-Fi which of course doesn't have tables that big.